/* This is just an example. You shouldn't do this.
#link-menu-button{
    list-style-image: url("chrome://link/skin/menubutton.png");
    -moz-image-region: rect( 0px 24px 24px  0px);
}

 common style for all custom buttons
.linkmenubutton
  {}

.linkmenubutton:hover
  {-moz-image-region: rect(24px 24px 48px  0px);}

[iconsize="small"] .linkmenubutton
  {-moz-image-region: rect( 0px 40px 16px 24px);}

[iconsize="small"] .linkmenubutton:hover
  {-moz-image-region: rect(24px 40px 40px 24px);}
 */
#linkmenubutton
{
  list-style-image: url("chrome://link/skin/icon.png");
}

toolbar[iconsize="small"] #linkmenubutton
{
 list-style-image: url("chrome://link/skin/icon-button.png");
}
toolbar[iconsize="small"] #linkmenubutton:active
{
 list-style-image: url("chrome://link/skin/icon-button-active.png");
}